During the past year, we have made progress in all three of our major research projects. As noted in our previous submissions, one of these involves the study of the transcriptional regulation of genes encoding the a-chain isoforms of the Na+, K+--ATPase. This project involves studies of promoters, enhancers, silencers, and cognate binding proteins. Considerable nucleotide sequence searching, vector and oligonucleotide design, and other GCG program use are required.